Rotary combustion engine having a charge-cooled rotor and side and peripheral wall intake ports

ABSTRACT

In a rotary internal combustion engine, having a charge-cooled rotor and intake ports in a housing side wall and housing peripheral wall, the intake ports are in communication with the rotor to receive all of the fuel-air mixture after it has flowed through the rotor. The flow through the intake port in the side wall is controlled by the rotor in its rotation within the housing while the flow through the intake port in the peripheral wall is throttled by a valve actuated in response to the speed or load of the engine so that, simultaneously with efficient cooling of the rotor, the engine derives the benefit of side intake and peripheral intake ports for smooth engine performance from idle to full speed.

United States Patent [191 Ward, III et al.

1 1 ROTARY COMBUSTION ENGINE HAVING A CHARGE-COOLED ROTOR AND SIDE ANDPERIPHERAL WALL INTAKE PORTS [75] Inventors: Harry M. Ward, III,Waukegan, 111.;

Eugene R. Hackbarth, Kenosha,

Wis.

[73] Assignee: Outboard Marine Corporation,

Waukegan, lll.

[22] Filed: Oct. 13, 1972 211 Appl. No.: 297,254

[52] US. Cl. 123/8.0l,'4l8/86 [51 I Int. Cl. F02b 55/06 [58] Field ofSearch 123/801, 8.45;

[56] References Cited UNITED STATES PATENTS 3,424,135 1/1969 Tado i.418/86 X 3,373 722 3/1968 Zimmermann ct al. 418/86 X FOREIGN PATENTS ORAPPLICATIONS 1,186,460 4/1970 Great Britain 418/86 1 Dec. 18, 1973Primary Examiner-Carlton R. Croyle Assistant Examiner-Michael Koczo, Jr.Attorney-Arthur Frederick et al.

[57] ABSTRACT In a rotary internal combustion engine, having acharge-cooled rotor and intake ports in a housing side wall and housingperipheral wall, the intake ports are in communication with the rotor toreceive all of the fuel-air mixture after it has flowed through therotor. The flow through the intake port in the side wall is controlledby the rotor in its rotation within the housing while the flow throughthe intake port in the peripheral wall is throttled by a valve actuatedin response to the speed or load of the engine so that, simultaneouslywith efficient cooling of the rotor, the engine derives the benefit ofside intake and peripheral intake ports for smooth engine performancefrom idle to full speed.

10 Claims, 5 Drawing Figures .AIENIEB DEC 18 0975 SHEET 3 OF 5PATENTEUDEC18 1975 3379214 SHEET 5 or 5 ROTARY COMBUSTION ENGINE HAVINGA CHARGE-COOLED ROTOR AND SIDE AND PERIPHERAL WALL INTAKE PORTSDISCLOSURE OF THE INVENTION This invention relates to rotary combustionengines, and more particularly to an improvement in rotary internalcombustion engines of the charge-cooled rotor type.

BACKGROUND OF THE INVENTION In rotary internal combustion engines of theWankel type, such as disclosed in U.S. Pat. No. 2,988,065 to Wankel etat., the cooling of the rotor has been achieved by the circulation oflubricant through the rotor, as exemplified in the U.S. Pats. toBentele, No. 3,176,915 and Sollinger, No. 3,176,916, or by the flow ofat least some of the fuel-air mixture through the rotor, the latterbeing referred to as a charge-cooled rotor. Charge-cooled rotors havebeen employed in combination with side and/or peripheral intake portsthrough which the fuel-air mixture enters the combustion chambers of theengine. Engines in which all of the fuel-air mixture required forcombustion is flowed through the charge-cooled rotor and thence througha side intake port or ports are exemplified in the U.S. Pats. toPaschke, No. 3,180,323, Zimmerman et al., No. 3,373,722, and No.3,405,694 and Keller et al., No. 3,652,190. Engines in which the totalfuel-air mixture is divided so that a portion or all of the fuel-airmixture is caused to flow through the charge-cooled rotor and a portionthrough a side intake port and peripheral intake port is disclosed inthe U.S. Pat. to Tado, No. 3,424,135 and the printed paper of theSociety of Automotive Engineers entitled, Improvements of the RotaryEngine With a Charge-Cooled Rotor, pre pared by Yamaoka and Tado, U.S.Pat. No. 720,466 and presented in May, 1972.

As is fully explained in the U.S. Pats. to Hamada, No. 3,424,136 andFroede, No. 3,244,153, an inherent characteristic of the rotarycombustion engine of the Wankel type is that the employment of intakeports of large flow area in the side or peripheral walls of the enginecasing or housing produces unstable operation, including sometimesmisfiring, during the idling or lowload phases of operation oftheengine, and provides high volumetric efficiency and correspondinglyhigh performance during high speed operation of the engine withfull-open throttle. This operating characteristic results from theoverlapping of induction and exhaust cycles, particularly when both theintake and exhaust ports are located in the peripheral housing wall.This partial overlap has little significance when the engine isoperating under heavy load, but results, at partial loads at low speed,in the transfer of some exhaust gas to the induction portion of thecycle of operation, mixing with the fresh gas and reducing the amount offresh fuel and air which can be drawn into the combustion chambers.Thus, an intake port in the housing side wall provides good idling orpartial load engine operation since the dilution of the fuel charge isminimal but results in loss of power at high speed because the geometryof the rotor limits the port size and the duration that it is open.Conversely, a peripheral intake port is not restricted in size by therotor geometry and, therefore, provides for superior engine performanceat high engine speed.

In the engines having charge-cooled rotors and intake ports located bothin the peripheral and the side housing walls, such as disclosed in theaforesaid patent to Tado, U.S. Pat. No. 3,424,135 and the aforesaidYamaoka et a1 S.A.E. paper, cooling efficiency of the rotor isdiminished when all of the fuel-air mixture is not utilized to cool therotor by reason of the fact that part of the fuel-air mixture bypassesthe rotor and enters directly into the induction combustion chamber. Infact when the rotor cooling requirements increase with engine speed, thecooling charge flow undesirably decreases as more of the fuel-airmixture is delivered to the peripheral intake port.

It is therefore an object of this invention to provide an improvedrotary internal combustion engine, having a charged-cooled rotor, inwhich maximum rotor cooling effect is achieved during all phases ofengine operation and at the same time provides stable and efficientengine operation from idle and partial load conditions through highload, high speed operation.

It is another object of the present invention to provide, in a rotaryinternal combustion engine, a chargecooled rotor capable of passing afuel-air mixture to a side intake port and a peripheral intake port.

A further object of the present invention is to provide a rotaryinternal combustion engine with a chargecooled rotor and wherein all ofthe fuel-air mixture is passed through the rotor and thence distributedbetween side and peripheral intake ports.

SUMMARY OF THE INVENTION In view of the foregoing, this inventioncontemplates a rotary internal combustion engine which combines acharge-cooled rotor with the advantages of intake ports in the side andperipheral walls of the housing so that improved rotor cooling isachieved together with providing smooth, maximum engine performanceduring idle and partial load operating conditions up to and includinghigh load, high speed operation.

The combination comprises a casing or housing having opposite side wallportions spaced apart by a peripheral wall to define therebetween acavity and within which a rotor is supported for eccentric rotation. Theinner surface of the peripheral wall has a trochoidal configuration withtwo or more lobes, while the rotor has a plurality of flank portionswhich number one more than the number of lobes. The rotor flank portionsdefine with the trochoidal inner surface of the peripheral wall, aplurality of working chambers which progressively increase and decreasein volumetric size as the rotor rotates within the cavity and therebyeach working chamber undergoes successively suction, compression,expansion and exhaust cycles of operation. A fuel-air mixture supplyport is provided in one of the housing side walls and is connectedthrough a suction conduit to a source of fuel and air, such as acarburetor. The rotor is provided with a plurality of axially extendingcooling passageways which are so located and sized sagcway, to receive aportion of the fuel-air mixture delivered to the transition-intake port.The transitionintake port is located and sized so that a portion of theport is always located radially inwardly of the inner envelope curve(path of travel) scribed by the gas seals carried in the end faces ofthe rotor and a portion is always located radially outwardly of theinner envelope curve scribed by the gas seals. The former portion formsthe transition port to receive the fuel-air mixture from the coolingpassageways of the rotor while the latter port portion constitutes theintake port to pass all or a portion of the fuel-air mixture from thetransition port portion to the working chamber under suction,hereinafter referred to as the induction chamber.

A valve means is provided to control flow of fuel-air mixture throughthe peripheral intake port so that, during the idling phase of engineoperation, the peripheral intake port can be closed and the engineoperates only on the fuel-air mixture delivered to the inductionchambers via the side intake port. Means may be provided forautomatically opening the valve means as engine speed increases fromidle so that at a predetermined engine speed or load full flow offuel-air mixture is provided through the peripheral intake port whilemaintaining fuel-air flow through the side intake port portion into theinduction chamber. Such means may be a linkage for interconnecting thevalve means with the throttle valve linkage so that actuation of thethrottle valve linkage simultaneously effects actuation of the valvemeans.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other objectives andadvantages of the present invention will appear more fully hereinafterfrom a consideration of the detailed description which follows whentaken together with the accompanying drawings wherein one embodiment ofthe invention is illustrated and, in iwhich:

FIG. 1 is a longitudinal cross-sectional view of the rotary internalcombustion engine according to this invention;

FIG. 2 is a transverse view in cross-section taken substantially alongline 2--2 of FIG. 1;

FIG. 3 is an enlarged fragmentary view in elevation showing the fuel-airmixture supply port shown in phantom lines in FIG. 2;

FIG. 4 is a fragmentary cross-sectional view taken substantially alongline 4-4 of FIG. 1; and

FIG. 5 is an exploded view in perspective of the rotary internalcombustion engine of this invention in which the major components andparts are schematically shown.

DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION Now referringto the drawings and, more particularly, to FIGS. 1 and 2, wherein therotary internal combustion engine of the Wankel type, such as disclosedin the US. Pat. to Wankel et al., No. 2,988,065 is generally designatedby the reference numeral 10. The rotary internal combustion engineessentially comprises a housing 12 within which a rotor 14 is supportedby an output shaft 16 for eccentric rotation.

The housing 12 comprises two side walls 18 and 20 which are held inspaced relationship by a peripheral wall 22. The side walls andperipheral wall 22 are secured together by tie bolts 24 to formtherebetween a cavity within which rotor 14 rotates. The peripheral wall22 has a trochoidal inner surface 26. As best shown in FIG. 2, innersurface 26 has a multi-lobe profile which preferably is an epitrochoidand for illustration purposes, the inner surface has two lobes whichmeet at lobe junctions 28.

The rotor 14 comprises a body having two axially spaced end faces 30 and32 and a peripheral surface consisting of a plurality of flank portions34, the next adjacent flank portions meeting at an apex portion 36. Theflank portions number one more than the number of lobes in the innertrochoidal surface 26 and, therefore, rotor 14 is shown herein as havingthree flank portions 34 since a two-lobe housing cavity is illustrated.The rotor 14 is supported within the housing cavity on an eccentricportion 38 of output shaft 16. To maintain the rotor in the properangular relationship to the housing and shaft, the rotor has an internalring gear 40 which meshes with a pinion gear 42 secured to housing endwall 18. The flank portions 34 define with trochoidal surface 26 ofhousing 12 a plurality of working chambers A, B and C which, uponrotation of rotor 18, successively increase and decrease in volumetricsize and, therefore, each working chamber undergoes a suction,compression, expansion and exhaust cycle of operation. To maintain theworking chambers A, B and C out of communication with each other, apexseals 44 are carried in each apex 36 of rotor 14 to abut the innersurface 26 and gas seals 46 are carried in each of the opposite endfaces 30 and 32 to engage the adjacent housing end walls 18 and 20.

As best shown in FIG. 2, housing 12 is air cooled and to this end sidewalls 18 and 20 are provided with fins 48, a blower or fan 49 connectedso as to be rotated by output shaft 16, and sheathing means 50 forguiding and directing air discharged from fan 49 over and between fins48.

In accordance with the present invention, rotor 14 is cooled by flow ofa fuel and air mixture therethrough and, therefore, the rotor 14constitutes a chargecooled rotor. To provide for flow of fuel and airthrough the rotor, rotor 14 has, adjacent each apex portion 36, coolingpassageways 52 which extend axially between opposite end faces 30 and 32of the rotor.

To provide for delivery of the fuel and air mixture required forproviding combustion in working chambers A, B and C, end wall 18 of thehousing has a supply port 54 which is so located and dimensioned that itregisters with each of the cooling passageways 52 of the rotor as thelatter rotates. In FIG. 2, supply port 54 is shown in phantom lines(dot-dash lines) while, in FIG. 3, the supply port 54 is shown in fulllines. The supply port 54 communicates with a source of fuel and air,such as a carburetor 56, via a conduit 58 which is formed in side wall18 and is connected at 61 to the carburetor to receive the fuel and airmixture. The supply port 54 is located such that it is always completelyradially, inwardly of the inner evelope curve traced by gas seals 46 asrotor 14 rotates within the housing cavity. This arrangement, of course,prevents communication of supply port 54 with working chambers A, B andC and bypass of fuel and air directly into those chambers.

As best illustrated in FIGS. 1, 4 and 5, a combination intake andtransition port 60 is provided in housing end wall 22 to receive thefuel-air mixture from cooling passageways 52 and pass the same to theworking chambers when the latter are in the suction, induction or intakecycle of operation (hereinafter referred to as the induction chamber).The intake and transition port 60 is located in substantial alignmentwith supply port 54 and is so located and sized that a portion of port60 is always completely within the inner envelope curve traced by gasseals 56 as rotor 14 rotates within the housing cavity. This portion ofport 60 constitutes the transition portion of the port, while theremaining portion of the port, which is radially outwardly of the innerenvelope curve scribed by the gas seals, functions as a side intake port62 (see FIG. 4). The flow of fuel and air through side intake port 62into the induction chamberis controlled by the geometry and speed ofrotation of rotor 16. i

In order that the engine have the benefits of the introduction of fueland air into the induction chamber peripherally as well as through sidewall intake port 62, the engine is provided with a peripheral intakeport 64 located in peripheral housing wall 22. The peripheral intakeport 64 is in communication with the transitionintake port 60, via adistribution conduit 66 which extends radially outwardly in housing sidewall and in an axial direction in peripheral wall 22. As best shown inFIGS. 1 and 5, distribution conduit 66 is partly defined by a cover 68secured to side wall 20. For purposes of controlling flow of fuel andair through peripheral intake port 64, a valve means, such as a throttleplate 70, is disposed in distribution conduit 66 and pivotally securedin peripheral wall 22. To achieve the advantages of both side andperipheral intake porting, the throttle plate 70 is in a position toclose-off flow of fuel and air through peripheral intake port 64 duringthe certain phases of engine operation, such as idling and deceleration,and is progressively opened as the engine operating conditions change,such as increased speed or load. Any suitable means for automaticallyactuating throttle valve 70 relative to the engine speed or loadconditions can be achieved by any suitable means well known to thoseskilled in the art. For example, through suitable linkage (not shown),throttle valve may be connected to the carburetor throttle valveactuating mechanism (not shown) so that the throttle valve 70 is movedsimultaneously with 'the carburetor throttle valve (not shown) betweentheir open or closed positions.

To effect ignition of the fuel and air mixture after its passage intoand compression in working chambers A, B and C, a spark plug 72 isprovided in peripheral wall 22 (see FIG. 2). The spark plug 72 formspart of any conventional ignition system well known to those skilled inthe internal combustion engine field. An exhaust means, including anexhaust port (not shown) and an exhaust duct 80 are provided inperipheral wall 22 to receive and conduct spent products of combustionfrom the working chambers A, B and C when they are in their exhaustcycle of operation.

Although, the invention has been described as applicable to anair-cooled engine, it is to be understood that the invention is not tobe limited to such engine and may be applied as well to liquid cooledengines. Also included in the scope of the invention are diesel enginesand engines having rotating housings and stationary rotors or where bothhousing and rotor rotate.

OPERATION In operation of engine 10, for the certain idling phase ofoperations, such as idling, throttle valve 70 is in the closed positionso that no fuel and air passes, through peripheral intake port 64, intothe induction chambers. As clearly illustrated in FIG. 5, the fuel-airmixture from carburetor 56 (FIG. 2) passes to supply port 54 via supplyconduit 58. From supply port 54, all of the fuel-air mixture flowsthrough cooling passageways 52 each time a passageway comes intoregistry with supply port 54 and intake-transition port 60. Of course,the ports 54 and 60 are so located relative to the angular position ofrotor 14 that registry occurs when intake port 62 and peripheral port 64are open to the induction chamber. In flowing through coolingpassageways 52, the fuel-air mixture removes heat from the rotor and isheated thereby. From intake-transition port 60, all of the fuel-airmixture flows into the induction chamber through the side intake port 62of intaketransition port 60 since throttle valve is closed. In an idlingphase of engine operation, entry of all of the fuelair mixture into theinduction chamber, through side intake port 62, provides the engine withstable and smooth operation. As the engine speed is changed and as sideintake port 62 becomes less able to provide the necessary amount offuel-air mixture for efficient, high power engine operation, throttlevalve 70 is opened to permit entry of fuel-air mixture into theinduction chamber, in addition to the fuel and air delivered to theinduction chamber through side intake port 62. This supplemental flow offuel and air, via distribution conduit 66, to peripheral intake port 64,increases with increased opening of throttle valve 70. With theincreased flow of fuel-air mixture through peripheral intake port 64,there is no sacrifice of rotor cooling since the entire fuel-air chargeis always directed through cooling passageways 52 of rotor 14. Also, theengine, from idle through high speed operation, always receives therequired amount of fuel and air for stable high power operation byreason of the controlled distribution of fuel and air to both the sideintake port 62 and peripheral intake port 64.

It is now believed readily apparent that the present invention providesan improved rotary internal combustion engine which combinescharge-cooling of the rotor with side and peripheral intake portswhereby effective cooling of the rotor is achieved particularly whenmost needed at high speeds or loads together with stable smooth engineperformance from idling through full speed operation of the engine.

Although but one embodiment of this invention has been illustrated anddescribed in detail, it is to be expressly understood that the inventionis not limited thereto. For example, additional cooling passageways canbe provided in the eccentric portion 38 of shaft 16 so that a portion ofthe fuel-air mixture effects a cooling of the rotor and rotor bearingssuch as disclosed in the printed paper of the Society of AutomotiveEngineers entitled, A Survey of Curtiss-Wrights 1958 1971 RotatingCombustion Engine Technological Developments, prepared by C. Jones, US.Pat. No. 720,468 May 1972, and in the US. Pat. to Paschke, No.3,180,323. Various other changes can be made in the arrangement of partswithout departing from the scope and spirit of the invention as'the samewill now be understood by those skilled in the art.

What is claimed is:

1. In a rotary internal combustion engine having side walls spaced apartby a peripheral wall to define therebetween a housing cavity withinwhich a rotor is supported for eccentric rotation, the rotor definingwith the housing cavity a plurality of working chambers whichsuccessively vary in volumetric dimensions as the rotor rotates andhaving axially extending passageway means extending therethrough, thecombination of a. a supply port means disposed in one of said side wallsso that as the rotor rotates it registers with the passageway means insaid rotor,

b. conduit means for communicating said supply port with a source ofcombustible fluid,

c. a side port means disposed in the other side wall so that as therotor rotates it registers with the passageway means in said rotor tothereby receive combustible fluid from the latter,

d. said side port means, including side intake port means, communicatingwith said working chambers to pass combustible fluid into the latter,

e. a peripheral intake port means in said peripheral wall communicatingwith said port means to receive from the latter a portion of saidcombustible f. control means for proportioning flow of combustible fluidto said peripheral intake port means and said side intake port means.

2. The apparatus of claim 1 wherein said control means is a valve whichregulates flow of combustible fluid through the peripheral intake portmeans.

3. The apparatus of claim 1 wherein said side port means, in addition tosaid side intake port means, includes a transition port means which isalways out of communication with the working chambers and registers withthe passageway means in the rotor as the latter rotates.

4. The apparatus of claim 3 wherein a distribution conduit meanscommunicates the transition port means with said peripheral intake portmeans.

5. The apparatus of claim 2 wherein actuating means is provided forclosing said valve during idling or deceleration of operation of theengine and for progressively opening the valve as the speed or load onthe engine increases.

6. The apparatus of claim 1 wherein said passageway means in the rotorincludes a plurality of axially extending passageways.

7. In a rotary internal combustion engine comprising side walls spacedapart by a peripheral wall having a trochoidal inner surface so as todefine therebetweeen a multi-lobed cavity and a rotor, having aplurality of circumferentially spaced apex portions, and opposite endfaces, supported for eccentric rotation in said cavity, the rotordefining with the trochoidal inner surface and the side walls aplurality of working chambers which successively vary in volumetric sizeas the rotor rotates and pass through suction, compression expansion andexhaust cycles of operation, the combination comprising a. a pluralityof cooling passageways extending axially through the rotor from onerotor end face to the other;

b. a supply port disposed in one of said side walls and in communicationwith a source of combustible fluid;

c. said supply port being of such size and location that itintermittently comes into registry with each of said plurality ofcooling passageways to pass combustible fluid into the latter;

(1. an intake-transition port in the other side wall disposed so that afirst portion of the port intermittently registers with each of saidplurality of cooling passageways to receive from the latter heatedcombustible fluid;

d. a second portion of said intake-transition port being locatedrelative to said rotor that the rotor allows communication of saidsecond port portion with the working chambers when the latter are in thesuction phase of operation and thereby provide for passage ofcombustible fluid into the working.

chambers,

f. a peripheral intake port in said peripheral wall communicating withsaid first port portion of the intake-transition port to receive aportion of the combustible fluid from the latter;

g. ignition means for igniting the combustible fluid after it passesinto the working chambers and is substantially compressed'by thecompression cycle of operation of the working chambers;

h. exhaust port means communicating with the working chambers duringtheir exhaust cycle of operation so as to expel burnt combustible fluidfrom the working chambers; and,

i. control means adjacent said peripheral intake port to regulate flowof combustible fluid to the peripheral intake port.

8. The apparatus of claim 7 wherein said peripheral intake port is incommunication with the first port portion of the intake-transition portvia a distribution conduit and wherein said control means is a valvedisposed in said distribution conduit.

9. The apparatus of claim 8 wherein said valve is connected to actuatingmeans for closing the valve during engine idling or deceleration and foropening the valve to its full open position gradually as engine speed orload increases.

10. The apparatus of claim 7 wherein said first portion of theintake-transition port is always out of communication with the workingchambers.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,779,214 Dated Dec. 18, 1973 Inventofls) Harry M. Ward, III and Eugene R.Hackbarth It is certified that error appears in the above-identifiedpatent and that said Letters Patent are hereby corrected as shown below:

IN THE SPECIFICATION:

Column 6 line 58, after the name "Jones", delete the words --U.S.Pat.--.

IN THE CLAIMS:

Column 7 line 19, after the word "said" insert the word side-.

Column 8, line 18, the letter "d." should read --e.-

Signed and sealed this 23rd day of April 19%..

(SEAL) Attest:

III/WARD PLFLEJTClMRJI-i. I IARSHALL DALIN Attesting OfficerCommissioner of Patents

1. In a rotary internal combustion engine having side walls spaced apartby a peripheral wall to define therebetween a housing cavity withinwhich a rotor is supported for eccentric rotation, the rotor definingwith the housing cavity a plurality of working chambers whichsuccessively vary in volumetric dimensions as the rotor rotates andhaving axially extending passageway means extending therethrough, thecombination of a. a supply port means disposed in one of said side wallsso that as the rotor rotates it registers with the passageway means insaid rotor, b. conduit means for communicating said supply port with asource of combustible fluid, c. a side port means disposed in the otherside wall so that as the rotor rotates it registers with the passagewaymeans in said rotor to thereby receive combustible fluid from thelatter, d. said side port means, including side intake port means,communicating with said working chambers to pass combustible fluid intothe latter, e. a peripheral intake port means in said peripheral wallcommunicating with said port means to receive from the latter a portionof said combustible fluid, and f. control means for proportioning flowof combustible fluid to said peripheral intake port means and said sideintake port means.
 2. The apparatus of claim 1 wherein said controlmeans is a valve which regulates flow of combustible fluid through theperipheral intake port means.
 3. The apparatus of claim 1 wherein saidside port means, in addition to said side intake port means, includes atransition port means which is always out of communication with theworking chambers and registers with the passageway means in the rotor asthe latter rotates.
 4. The apparatus of claim 3 wherein a distributionconduit means communicates the transition port means with saidperipheral intake port means.
 5. The apparatus of claim 2 whereinactuating means is provided for closing said valve during idling ordeceleration of operation of the engine and for progressively openingthe valve as the speed or load on the engine increases.
 6. The apparatusof claim 1 wherein sAid passageway means in the rotor includes aplurality of axially extending passageways.
 7. In a rotary internalcombustion engine comprising side walls spaced apart by a peripheralwall having a trochoidal inner surface so as to define therebetweeen amulti-lobed cavity and a rotor, having a plurality of circumferentiallyspaced apex portions, and opposite end faces, supported for eccentricrotation in said cavity, the rotor defining with the trochoidal innersurface and the side walls a plurality of working chambers whichsuccessively vary in volumetric size as the rotor rotates and passthrough suction, compression expansion and exhaust cycles of operation,the combination comprising a. a plurality of cooling passagewaysextending axially through the rotor from one rotor end face to theother; b. a supply port disposed in one of said side walls and incommunication with a source of combustible fluid; c. said supply portbeing of such size and location that it intermittently comes intoregistry with each of said plurality of cooling passageways to passcombustible fluid into the latter; d. an intake-transition port in theother side wall disposed so that a first portion of the portintermittently registers with each of said plurality of coolingpassageways to receive from the latter heated combustible fluid; d. asecond portion of said intake-transition port being located relative tosaid rotor that the rotor allows communication of said second portportion with the working chambers when the latter are in the suctionphase of operation and thereby provide for passage of combustible fluidinto the working chambers, f. a peripheral intake port in saidperipheral wall communicating with said first port portion of theintake-transition port to receive a portion of the combustible fluidfrom the latter; g. ignition means for igniting the combustible fluidafter it passes into the working chambers and is substantiallycompressed by the compression cycle of operation of the workingchambers; h. exhaust port means communicating with the working chambersduring their exhaust cycle of operation so as to expel burnt combustiblefluid from the working chambers; and, i. control means adjacent saidperipheral intake port to regulate flow of combustible fluid to theperipheral intake port.
 8. The apparatus of claim 7 wherein saidperipheral intake port is in communication with the first port portionof the intake-transition port via a distribution conduit and whereinsaid control means is a valve disposed in said distribution conduit. 9.The apparatus of claim 8 wherein said valve is connected to actuatingmeans for closing the valve during engine idling or deceleration and foropening the valve to its full open position gradually as engine speed orload increases.
 10. The apparatus of claim 7 wherein said first portionof the intake-transition port is always out of communication with theworking chambers.